HPV Vaccine
About There are two types of human papilloma virus (HPV) vaccines currently available: Gardasil and Cervatrix. HPV is associated with the onset of cervical cancer and genital warts. It is the most common sexually transmitted disease in adults. Therefore, the World Health Organization (WHO) recommends all young women to receive to vaccine. Although the vaccine is thought of to only be for females, it is also approved for male usage, especially in the United States where rate of vaccination in women are low and in those populations at risk for HPV-associated cancers. Usage Gardasil and Cervarix are both vaccines that prevent HPV infection, but doesn't treat either. Both vaccines protect against HPV-16 and HPV-18 (2 HPV types). Gardasil also protects again HPV06 and HPV-11, which makes it protective against 4 HPV types. HPV-16 and HPV-18 are known to cause cervical cancer, anal cancer, vaginal cancer, and vulvar cancers. HPV-6 and HPV-11 are known to cause genital warts. Gardasil and Cervarix both offer at least 4.5 years of protection after three doses of vaccination (needed in order to for the body to produce enough antibodies) in a span of six months. They're recommended for women before they are sexually active and exposed to HPV (ages 9-26). In males, HPV has been approved in many countries (United States, United Kingdom, South Korea, and Australia). Gardasil is FDA-approved for usage in males ages 9-26 for prevention of genital warts and anal cancer. Even older women can use the vaccine because recent data shows the HPV vaccine to be effective in protecting against cervical cancer in women up to 45 years-old. Genetics HPV vaccines' contents are based upon recombinant HPV coat proteins, which allows assembly of virus-like particles (VLPs). The human papilloma virus itself contains circular double stranded DNA and contains a capsid composed of 72 capsomeres, which is a subunit of the capsid. Every viral subunit contains two proteins, L1 and L2. The structure of these proteins allow the virus to infect the skin and mucous layers. The structure of the virus was essential for development of the vaccines. Gardasil Gardasil's proteins are synthesized by recombinant Saccharomyces cerevisiae, a yeast, and contains inactive L1 proteins from four different HPV strains (HPV-6, 11, 16, and 18). This allows Gardasil to target all four strains. L1 is a major HPV capsid protein and can spontaneously assemble themselves into virus-like proteins (VLPs), which closely resemble actual HPV viruses. Gardasil contains recombinant VLPs from the L1 proteins of HPV strains 6, 11, 16, and 18. VLPs don't contain viral DNA so they cannot induce cell proliferation, which can lead to cancer. They trigger a useful antibody response in those who are vaccinated and protects them from HPV infections presented in the cell. Each L1 protein is synthesized separately by ''Saccharmoyces cerevisiae ''before they assemble themselves into VLPs. Cervarix Cervarix is produced using recombinant DNA technology that uses L1 protein of the HPV oncogenic strains 16 and 18. The L1 proteins used are produced in separate bioreactors using a recombinant Baculovirus expression vectors system that uses Hi-5 Rix4446 cells derived from the Trichoplusia ni. insect. The vaccine doesn't contain virus or DNA and thus cannot cause cell proliferation, leading to cancer. Purification Cerarix Purification occurs after L1 proteins are released from Trichoplusia ni insect cells. The L1 proteins are purified using chromatographic and filtration methods. L1 protein assembly into VLPs occurs at the end of purification. References 1. Wikipedia article: HPV Vaccines. Date accessed: Dec 6, 2014. 2. Wikipedia article: Gardasil. Date accessed: Dec 6, 2014. 3. Wikipedia article: Cervarix. Date accessed: Dec 6, 2014. 4. FDA - Cervarix Perscribing Information. Date accessed: Dec 6, 2014.